The effects of micro-alloying elements such as Ti, Nb, Al, Cu on corrosion properties were investigated. The intergranular corrosion attack(IGC) was examined with several tests such as strauss test, EPR(Electropotentiokinetic Reactivation), 40% HNO₃...
The effects of micro-alloying elements such as Ti, Nb, Al, Cu on corrosion properties were investigated. The intergranular corrosion attack(IGC) was examined with several tests such as strauss test, EPR(Electropotentiokinetic Reactivation), 40% HNO₃etching to find out the optimum of the stabilizing ratio(=(Ti+ Nb)/(C+N)). The effects of A1 and Cu were studied with inclusion analysis, corrosion tests, passive film analysis. The minimum stabilizing ratio was 9 and the dual stabilization was required to more effectively prevent intergranular corrosion attack. The addition of A1 and Cu improved crevice corrosion resistance as well as pitting resistance. The effect of A1 and Cu could be explained with decrease of area fraction covered by inclusion and redeposition of Cu, respectively.